Courier: Argosy. Easy to manouver through blocades and fast enough to get away from lock- on missiles. And the cargo space is large enough to accept a few missions as well.
Fighter: Lightning. Fast. Reasonably equipped with guns and weapons and can give a solid blow to other ships. Tested it without using the "distance shoot em in the front" manouver and I knocked out Argosy's, Hawks, Defenders, other Lightnings, Confed Fighter, 4 Mantas and believe or not, a Kestrel. Only crap thing about it is the lack of cargo hold.
Warship: Rebellion Cruiser ( with acceleration, engine and turning upgrade, a layer of tritanium and ONLY proton turrets or guns. ) Though the shields arent as good as the Confed Cruiser, this ship offers better conditions under attack. If you keep the Manta fighters and buy some Hawks as well, no one can mess around with you. Also good cargo hold so you can use that to get some more upgrades.
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From MarVin...